class withsomething(object):
  def __init__(self,other):
    self.other=other();
  def __str__(self):
    return other.__str__ + super.__str__;

@withsomething
class withsugar(object):
  def __str__(self):
    return " with sugar";

@withsomething
class withmilk(object):
  def __str__(self):
    return " with milk";

class coffee(object):
  def __str__(self):
    return "coffee";

print withmilk(coffee());